We've seen the movies a hundred times action stars driving cars and oceans -- rivers. -- -- -- the bad guys in hot pursuit inevitably the automotive -- continues under -- is the hero adroitly escapes. And swims to shore. That's Hollywood but ABC's Lisa stark -- experts -- show us the real thing is far from easy. But knowing how to do it could save your life. What -- you had just. Thirty seconds to save your life. If your car -- crashed into deep water that's about all the time you happy. Thirty seconds may be one minutes to get yourself and your family I don't -- -- The very critical. -- to get out of this -- very very fast as soon as you realize your vehicles in the water just Beringer is a diver with a sheriff's department in Naples Florida. He and other emergency responders are learning how to escape before. -- terrifying accidents happen more than you think as many as 400. Deaths a year in North America. I got by the department and. I think -- and I -- And usually by the time rescuers find the vehicle it is completely underwater. It's too late to just -- -- so there are safety precautions as Jeff gets trapped in the car's back window removed as a last ditch escape route. And rescue divers in the water. From the -- it's frightening to watch as the car began sinking. Inside. More terrifying as the water rushes in. She hasn't follows the simple but crucial procedure and seatbelt -- and window down and get out. There's relief when he surfaces from the eight foot deep canal. -- about it was a very intimidating. That are. Went down for that I thought it would know we're gonna make a little more complicated. What is there are more passengers. Even children. Can happen when really get out in time Wednesday night aren't in this test the car is filled with the driver and three passengers. Let's start the clock. Almost instantly seatbelts off and windows down within eight seconds both front seat passengers are out water now rushing in. The backseat passengers scramble within twelve seconds the third passenger is out the last one in sixteen seconds. Everyone is safe -- under twenty seconds -- Let's watch it again this time in slow motion. Those inside the car have to fight against the current but they -- push through it can be done. According -- -- was the fourth man out of that -- he's a veteran it tips the Canadian researcher has spent the last. Callers often that he himself inside then try to figure out the best way to survive. Real -- there would be mechanic. -- drivers might freeze out. When we're scared is not the time to be figuring things out. That's why returned to get this message into the psyche of the public. Gordon who's running this demonstration drills that message home. She -- open the window. And here Gordon says all too often people understand. Do the wrong things. Should just wasted precious seconds dialing for helped. So the first thing is don't touch yourself forward don't call 911 don't how -- -- do not call 911 from inside the sinking vehicle. And don't open the doors it's almost impossible to do anyway against the water pressure and it will sink the car faster and look what happened in this test. The door -- -- There's also mistaken belief that you can let the vehicle sink filled with dirty equalized the pressure and then get the doors open -- Dallas. If you have this magic careful. -- if you wait for this magic here over the finally get a -- the -- -- could open the doors to let. For these demonstrations the car has rolled down windows most cars these days have power windows there is no -- -- -- Working -- water. I'm manufacturers tell -- most should -- briefly. But what are they don't. -- recommends as simple inexpensive window break tool. This one is called rescue me I tried to exhaust them back and -- -- Mario packed. -- device -- more easily and quickly accessible perhaps a rear view mirror. Tests are needed to. To -- -- change starting next month 911 operators will begin learning new procedures. If someone in -- sinking vehicle calls in. Operators will tell them to -- -- long windows down and get out. Advice based on hundreds of tests like these. For Nightline I'm Lisa stark in Naples Florida.

This transcript has been automatically generated and may not be 100% accurate.

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